Add default avatar and zuul avatar

Change-Id: Ied34bdcb915eb8982fd2855951ad189d3ce2f022
diff --git a/config_avatars.php b/config_avatars.php
index a978b99..ee1e5d4 100644
--- a/config_avatars.php
+++ b/config_avatars.php
@@ -2,6 +2,9 @@
 // Avatars definitions
 $USERS = [
   'avm99963' => 'https://www.avm99963.com/images/avatar.jpg',
-  'ccbot' => 'https://developers.google.com/search/images/google-search-central-logo.png',
-  // Add your avatar above!
+  'ccbot' => 'https://gerrit-avatars.avm99963.com/img/webmasters.png',
+  'zuul' => 'https://gerrit-avatars.avm99963.com/img/zuul.svg',
+  // Add your avatar above this line!
 ];
+
+$DEFAULT_AVATAR = 'https://gerrit-avatars.avm99963.com/img/default.png';